Photoelectron yields of scintillation counters with embedded wavelength-shifting fibers read out with silicon photomultipliers

Abstract

Photoelectron yields of extruded scintillation counters with titanium dioxide coating and embedded wavelength shifting fibers read out by silicon photomultipliers have been measured at the Fermilab Test Beam Facility using 120 GeV protons. The yields were measured as a function of transverse, longitudinal, and angular positions for a variety of scintillator compositions, reflective coating mixtures, and fiber diameters. Timing performance was also studied. These studies were carried out by the Cosmic Ray Veto Group of the Mu2e collaboration as part of their R&D program.

Performance of wavelength-shifting fibers for the Mu2e cosmic ray veto detector

“…Approximately 1 km of 1.4 mm fiber was purchased to produce the CRV pre-production prototype detectors. Response for these prototypes was also measured in the test beam and found to meet requirements [11]. One spool of 1.4 mm pre-production fiber, whose performance was measured in the test beam, was identified as a benchmark spool against which all production fiber could be compared.…”

“…Counters with 1.0 mm, 1.4 mm, and 1.8 mm fiber were fabricated and evaluated in the Fermilab Test Beam Facility [11] using a 120 GeV proton beam. The 1.4 mm diameter fiber was selected for use in the CRV based on the test beam results and requirements that were derived from detailed simulations of the CRV performance [1].…”

A high efficiency photon veto for the Light Dark Matter eXperiment

“…The bars have a through-hole into which a wavelength-shifting fiber is inserted, which is read out at the ends with Silicon-Photomultipliers (SiPMs). This design is similar to what is used in the Mu2e Cosmic Ray Veto system [12,13]. The bars are arranged in an (x, y) configuration, with the longitudinal position within a bar constrained by means of timing correlations for signals arriving at the two ends of each bar.…”

Mu2e: A Search for Charged Lepton Flavor Violation in $μN → eN$ Conversion with a Sensitivity $< 10^{-16}$

“…Mu2e: A Search for Charged Lepton Flavor Violation in µN → eN with a Sensitivity < 10 −16 G. Pezzullo that makes 2-3 loops in the tracking chamber and then hit the calorimeter, producing an electromagnetic shower. The R&D of the sub-detectors is mature [4,5,6] and the production phase has already begun in 2018.…”